1985 300D: Front bumper strip insert?

[dogguy]

Since my state does not require a front license plate, I have neither a plate or the bracket installed.

My question: Did Mercedes ever offer any sort of an insert for the indented area of the impact strip that is exposed when there is no bracket and plate installed? There appears to be no insert shown in any of the EPC images I have found, so maybe not. The two attached pictures show what I am referring to.

If anyone has any clarifications or insights about this, I would appreciate your sharing.
Thank you.